CERAMICS INTERNATIONAL
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2013
·
IF 1.789
Mingye Ding,Chunhua Lu,Qiaoqiao Cui,Yaru Ni,Zhongzi Xu
Glasses within the B 2 O 3 –Al 2 O 3 –Na 2 O system were examined as potential replacements for PbO-based glass frits with low firing temperature (500–600 °C) for transparent dielectric layer of plasma display panel (PDP). The glasses were evaluated for glass transition ( T g ), softening temperature ( T f ), thermal coefficient of expansion ( α ) and dielectric constant ( ε ). The dielectric constant of these glasses was also compared with theoretical data calculated by Appen and Bresker's equation. T g of the glasses varied between 330 and 460 °C and T f was in the region of 350–500 °C. The thermal coefficient of expansion ranged from 7×10 −6 to 10×10 −6 K −1 . The dielectric constant of these glasses was 6–8 within the region of the theoretical value. The T g , T f , α , ε of the selected glass, which was used to prepare transparent dielectric layer in 20 μm thickness, were found to be 449 °C, 476 °C, 8.284×10 −6 /k, 6.84, respectively. All the results suggest that B 2 O 3 –Al 2 O 3 –Na 2 O glasses would be suitable as a potential candidate for Pb-free dielectric layer in PDPs.
研究领域:
材料科学
·
电子工程
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DOI
高影响因子
JOURNAL OF LUMINESCENCE
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2024
·
IF 3.3
Heng Guo
Low-dimensional metal halides, which possess efficient luminescent properties, have garnered significant interest in the fields of optoelectronics and radiation detection. This study introduces novel lead-free silver-based metal halide material, CsAgCl 2 microcrystals (MCs). These MCs have a one-dimensional atomic chain structure and a unique [AgCl 5 ] 4- tetragonal shared triangular configuration. CsAgCl 2 MCs exhibit excellent performance as X-ray scintillators due to their bright broadband yellow emission and fast decay time in the microsecond range. The large Stokes shift of 350 nm is produced by self-trapped exciton emission. In X-ray scintillation applications, CsAgCl 2 MCs demonstrate a high light yield of 13280 photons/MeV and a wide range of linear scintillation response. It is noteworthy that the CsAgCl 2 MCs maintain good stability under both atmospheric conditions and continuous X-ray irradiation. The sample was used in an X-ray imaging screen, which clearly presented the X-ray projection image of a wooden stick. As a result, this research not only contributes to the collection of lead-free metal halide scintillators but also indicates that CsAgCl 2 MCs have a wide range of future applications and potential in areas such as medical imaging, scientific research, and diagnostic and detection technologies.
研究领域:
材料科学
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辐射检测
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医学影像
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产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2022
·Vol. 51
·期 12
·4878-4883
·
IF 4.569
Jia-Jing Wu,Yue Guo,Wen-Dong Yao,Wen-Long Liu,Sheng-Ping Guo
Low-dimensional organic–inorganic metal halides, especially lead-free perovskites, are attracting increasing attention because of their environmentally friendly processing, flexible structures, chemical stability, and promising nonlinear optical properties. Herein, we report a new stable polar 0D lead-free hybrid bismuth chloride to enable the second-harmonic generation (SHG) active material (BTA)3Bi2Cl9 (BTA = benzyltriethylammonium, C6H5CH2N(C2H5)3+) that was obtained by the antisolvent vapor diffusion method and crystallized in the polar Cc space group. Its structure features organic cations surrounded by face-sharing [Bi2Cl9]3− dimers. (BTA)3Bi2Cl9 exhibits a wide direct bandgap (3.21 eV) and a strong phase-matchable SHG conversion efficiency (1.39 × KDP). Theoretical calculation reveals that the SHG response is owing to the synergistic effect of distorted inorganic [Bi2Cl9]3− anions and polar organic BTA+ cations. This work not only enriches the family of organic–inorganic A3M2X9 (A = monovalent cations; M = trivalent metal ions; and X = halide ions) NLO crystals but also provides the possibilities for further designing novel lead-free semiconducting piezoelectric, pyroelectric and ferroelectric materials.
研究领域:
材料科学
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晶体化学
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光学材料
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DOI
高影响因子
Chemistry-Switzerland
·
2025
·Vol. 7
·期 5
·150
·
IF 2.4
Ting Geng,Yuhan Qin,Zhuo Chen,Yuhan Sun,Ao Zhang,Mengyuan Lu,Mengzhen Lu,Siying Zhou,Yongguang Li,Guanjun Xiao
Lead-free perovskite variants have emerged as promising candidates due to their self-trapped exciton emission. However, in ASnX3systems, facile oxidation of Sn(II) to Sn(IV) yields A2SnCl6vacancy-ordered derivatives. Paradoxically, despite possessing a direct bandgap, these variants exhibit diminished photoluminescence (PL). Doping engineering thus becomes essential for precise optical tailoring of A2SnX6materials. Herein, through integrated first-principles calculations and spectroscopic analysis, we elucidate the luminescence mechanism in Te4+-doped (NH4)2SnCl6lead-free perovskites. Density functional theory, X-ray diffraction (XRD) patterns and X-ray photoelectron spectroscopy (XPS) confirm Te4+substitution at Sn sites via favorable chemical potentials. Spectral interrogations, including absorption and emission profiles, reveal that the intense emission originates from the triplet STE recombination (3P1→1S0) of Te centers. Temperature-dependent PL spectra further demonstrate strong electron–phonon coupling that induces symmetry-breaking distortions to stabilize STEs. Complementary electronic band structure and molecular orbital calculations unveil the underlying photophysical pathway. Leveraging these distinct thermal responses of PL intensity and peak position, 0.5%Te:(NH4)2SnCl6emerges as a highly promising candidate for non-contact, dual-parameter optical thermometry over an ultra-broad range (100–400 K). This work provides fundamental insights into the exciton dynamics and thermal engineering of optical properties in this material system, establishing its significant potential for advanced temperature-sensing applications.
研究领域:
材料科学
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凝聚态物理
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光学工程
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无机化学
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功能材料
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）